Job Entry Subsystem 1

Job Entry Subsystem (JES), aka Job Entry Subsystem 1 (JES1), was released by IBM as an integral part of OS/VS1 as an enhancement to the basic functions that users of VS1's predecessor, MFT, had.

History

IBM proclaimed JES1 to be "the single most important addition" to the job scheduling provided by VS1. IBM Systems Journal defined JES1's services as Spooling and scheduling, adding "Its three major components are peripheral services, central services, and queue management."

JES1 was not popular,^: 5 because HASP and ASP users often had made local modifications (edits),^: 9 and wanted to retain their investment.

Features

JES1 permits operators to submit batch jobs from local unit record equipment.

In addition, Remote Entry Service (RES) permits remote operators to submit jobs from remote sites to JES. The printed and punched output of jobs running on OS/VS1, whether submitted locally or remotely, is handled by JES and may be routed to local devices, to the originating site or to another remote site. The Remote Entry Services (RES) of OS/VS1 is similar to Remote Job Entry (RJE) on OS/360 but the protocol for programmable workstations is that used by HASP II and Attached Support Processor (ASP) rather than that used by RJE.

New Features

In MFT a reader or writer task tied up a partition; in JES1 a separate partition was required only while starting or stopping the task.
In MFT each SPOOL file was a separate physical sequential (PS) dataset on public DASD; in JES1 SPOOL files are kept in a common SYS1.SYSPOOL dataset managed by JES1.
In MFT a reader task could be delayed by interpreting tasks; in OS/VS1 the interpretation is done when the job is initiated.
The JOB Card JCL was given a new option: TYPRUN=SCAN, whereby a job could be submitted for quick feedback, and - if no errors were detected - be submitted again (without TYPRUN=SCAN on the JOB Card.^: 399
JES1 used a SubSystem Interface (SSI) similar to that in MVS.

Spooling

Job Entry Central Services (JECS) does its own I/O for files contained within SYS1.SYSPOOL and provides an Access Control Block (ACB) / Request Parameter List (RPL) API to other services, e.g., Job Entry Peripheral Services (JEPS).

The term system input (SYSIN) refers to

The JCL for a job
Instream datasets in the job
Procedures defined in the job.

A JEPS reader transcribes jobs to SPOOL using JECS but does not interpret them. It stores each instream dataset as a separate file.

The term system output (SYSOUT) refers to

Print dataset written by the job
Punch datasets written by the job
Messsages written on behalf of the job, including an optional transcription of the JCL

A JEPS writer transcribes SYSOUT data set from SPOOL using JECS.

JES1 provides a Compatibility Interfaces that allows jobs to continue to use the old DCB interface; OPEN creates an ACB/RPL pair that the access method uses on behalf of the application.

Notes

↑ VSAM and VTAM introduced te ACB as a replacement for the Data Control Block (DCB), and the RPL as a parameter for I/O macros using the ACB.

References

Features: OS/Virtual Storage 1 - Features Supplement (PDF). Systems (Fourth ed.). IBM. January 1977. GC20-1752-3. Retrieved November 15, 2025.
Networking: Hutchinson, John M. (March 1980). Job Networking Facilities (PDF). Technical Bulletin (First ed.). IBM Washington Systems Center. GC24-5090-1. Retrieved November 15, 2025.
Planning: OS/VS1 Planning and Use Guide - VS1 Release 2 (PDF). Systems (Second ed.). IBM. January 1973. GC24-5090-1. Retrieved November 15, 2025.

Citations

↑ IBM 3800 Printing Subsystem Programmer's Guide (PDF) (Fourth ed.). IBM. January 1980. GC26-3846-3. Archived (PDF) from the original on 2019-05-25. Retrieved 2020-06-28. JES1, the job entry subsystem for OS/VS1.
1 2 T. F. Wheeler, Jr. (1973). IBM OS/VS1 - An evolutionary growth system. International Workshop on Managing Requirements Knowledge. New York, NY: AFIPS. p. 395. doi:10.1109/AFIPS.1973.92.
↑ Baily, J. H.; Howard, J. A.; Szczygielski, T. J. (1974). "The job entry subsystem of OS/VS1". IBM Systems Journal. 13 (3): 253–269. doi:10.1147/sj.133.0253. ISSN 0018-8670.
1 2 3 Tom Wasik. "JES2 Bootcamp - Part 1 of 3: What is JES2 and what does it do" (PDF). Archived (PDF) from the original on 2022-12-16. Retrieved 2019-10-06.
↑ above IBM document, page 5. Also, there was a HASP modification "clearinghouse" at University of Chicago, from which other HASP users "downloaded" (actually printed^{[citation needed]}. via RJE and rekeyed ("Keypunched"); this was before the term download was in use).
↑ Networking, p. 13, 2.0 Remote Job Entry - Product Comparisons -- 2.1 Characteristics/Design Objectives "RJE is usually part of the system or job entry subsystem"
↑ which also (p.7) describes this as being an "early 'client server' which "Uses BSC and SNA protocols," adding "still used today." (2013)
↑ Planning and Use Guide 1973, p. 18, Remote Entry Services (RES).
↑ OS/VS1 Job Management Logic - VS1 Release 2 (PDF). Systems (Second ed.). IBM. January 1973. SY24-5161-1. Archived (PDF) from the original on December 7, 2025. Retrieved July 14, 2026.

[9] VSAM and VTAM introduced te ACB as a replacement for the Data Control Block (DCB), and the RPL as a parameter for I/O macros using the ACB.

[1] IBM 3800 Printing Subsystem Programmer's Guide (PDF) (Fourth ed.). IBM. January 1980. GC26-3846-3. Archived (PDF) from the original on 2019-05-25. Retrieved 2020-06-28. JES1, the job entry subsystem for OS/VS1.

[AFIPS-2] 1 2 T. F. Wheeler, Jr. (1973). IBM OS/VS1 - An evolutionary growth system. International Workshop on Managing Requirements Knowledge. New York, NY: AFIPS. p. 395. doi:10.1109/AFIPS.1973.92.

[BailyHoward1974-3] Baily, J. H.; Howard, J. A.; Szczygielski, T. J. (1974). "The job entry subsystem of OS/VS1". IBM Systems Journal. 13 (3): 253–269. doi:10.1147/sj.133.0253. ISSN 0018-8670.

[SHARE.rpt-4] 1 2 3 Tom Wasik. "JES2 Bootcamp - Part 1 of 3: What is JES2 and what does it do" (PDF). Archived (PDF) from the original on 2022-12-16. Retrieved 2019-10-06.

[5] ve IBM document, page 5. Also, there was a HASP modification "clearinghouse" at University of Chicago, from which other HASP users "downloaded" (actually printed^{[citation needed]}. via RJE and rekeyed ("Keypunched"); this was before the term download was in use).

[6] Networking, p. 13, 2.0 Remote Job Entry - Product Comparisons -- 2.1 Characteristics/Design Objectives "RJE is usually part of the system or job entry subsystem"

[7] which also (p.7) describes this as being an "early 'client server' which "Uses BSC and SNA protocols," adding "still used today." (2013)

[FOOTNOTEPlanning_and_Use_Guide1973[httpbitsaversorgpdfibm370OS_VS1GC24-5090-1_OS_VS1_Planning_and_Use_Guide_197301pdfpage19_18]Remote_Entry_Services_(RES)-8] Planning and Use Guide 1973, p. 18, Remote Entry Services (RES).

[10] OS/VS1 Job Management Logic - VS1 Release 2 (PDF). Systems (Second ed.). IBM. January 1973. SY24-5161-1. Archived (PDF) from the original on December 7, 2025. Retrieved July 14, 2026.